Secondary battery with modular terminal assembled and method of manufacturing the same

Abstract

A secondary battery including a case with an opening, an electrode assembly accommodated in the case, and a cap assembly having a cap plate joined to the opening of the case, the cap plate including a terminal accommodating hole, and a terminal module electrically connected to the electrode assembly, the terminal module having a top surface joint portion insertable into the terminal accommodating hole of the cap plate, the top surface joint portion being joined to a top surface of the cap plate and having an internal through-hole space, a bottom surface joint portion inserted into the terminal accommodating hole and joined to a bottom surface of the cap plate, a terminal plate in the internal through-hole space of the top surface joint portion, and an insulator between the terminal plate and each of the top surface joint portion and the bottom surface joint portion.

What is claimed is: 
     
         1 . A secondary battery comprising:
 a case with an opening;   an electrode assembly accommodated in the case; and   a cap assembly including:
 a cap plate joined to the opening of the case, the cap plate including a terminal accommodating hole, and 
 a terminal module electrically connected to the electrode assembly, the terminal module including:
 a top surface joint portion insertable into the terminal accommodating hole of the cap plate, the top surface joint portion being joined to a top surface of the cap plate and having an internal through-hole space, 
 a bottom surface joint portion inserted into the terminal accommodating hole and joined to a bottom surface of the cap plate, 
 a terminal plate in the internal through-hole space of the top surface joint portion, and 
 an insulator between the terminal plate and each of the top surface joint portion and the bottom surface joint portion. 
 
   
     
     
         2 . The secondary battery as claimed in  claim 1 , wherein the top surface joint portion of the terminal module includes a vertical wall surrounding the internal through-hole space, the vertical wall being bent radially outwardly from the through-hole space and joined to the top surface of the cap plate. 
     
     
         3 . The secondary battery as claimed in  claim 1 , wherein the insulator of the terminal module is between an inner circumferential surface of the top surface joint portion and an outer circumferential surface of the terminal plate. 
     
     
         4 . The secondary battery as claimed in  claim 3 , wherein the insulator of the terminal module includes an outer portion in contact with the outer circumferential surface of the top surface joint portion. 
     
     
         5 . The secondary battery as claimed in  claim 1 , wherein the insulator of the terminal module is integral with the bottom surface joint portion and the top surface joint portion. 
     
     
         6 . The secondary battery as claimed in  claim 1 , wherein the terminal accommodating hole in the cap plate includes an upper recessed portion in the top surface of the cap plate and a lower recessed portion in the bottom surface of the cap plate. 
     
     
         7 . The secondary battery as claimed in  claim 1 , wherein a top surface of the terminal plate of the terminal module is flush with the top surface of the cap plate. 
     
     
         8 . The secondary battery as claimed in  claim 1 , wherein a top surface of the terminal plate of the terminal module is lower than the top surface of the cap plate. 
     
     
         9 . The secondary battery as claimed in  claim 1 , wherein the terminal plate of the terminal module includes an interfacial metal layer. 
     
     
         10 . The secondary battery as claimed in  claim 1 , further comprising at least one of a first sealing member, a second sealing member, and a third sealing member, the first sealing member being between an outer circumferential surface of the terminal module and the cap plate, the second sealing member covering a top surface of the top surface joint portion of the terminal module, and the third sealing member covering a bottom surface of the bottom surface joint portion of the terminal module. 
     
     
         11 . A method of manufacturing a secondary battery, the method comprising:
 manufacturing a case with an opening;   manufacturing an electrode assembly to be accommodated in the case;   manufacturing a cap plate with a terminal accommodating hole;   manufacturing a terminal module electrically connected to the electrode assembly;   assembling the terminal module to the cap plate; and   inserting the electrode assembly into the case and joining the cap plate to the opening of the case,   wherein assembling the terminal module to the cap plate includes:
 inserting the terminal module into the terminal accommodating hole formed in the cap plate and joining the terminal module to a top surface of the cap plate; and 
 joining the terminal module inserted into the terminal accommodating hole to a bottom surface of the cap plate. 
   
     
     
         12 . The method as claimed in  claim 11 , wherein:
 manufacturing the terminal module includes forming a top surface joint portion of the terminal module, such that the top surface joint portion includes a vertical wall surrounding an internal through-hole space, and   inserting the terminal module into the terminal accommodating hole includes:
 inserting the vertical wall of the terminal module into the terminal accommodating hole; and 
 bending the vertical wall radially outwardly from the through-hole space and joining the terminal module to the top surface of the cap plate. 
   
     
     
         13 . The method as claimed in  claim 11 , wherein manufacturing the terminal module includes:
 forming a top surface joint portion insertable into the terminal accommodating hole formed in the cap plate and joinable to the top surface of the cap plate, the top surface joint portion having an internal through-hole space;   forming a bottom surface joint portion insertable into the terminal accommodating hole and joinable to the bottom surface of the cap plate;   forming a terminal plate in the internal through-hole space of the top surface joint portion; and   forming an insulator configured to electrically insulate the terminal plate from the top surface joint portion and the bottom surface joint portion.   
     
     
         14 . The method as claimed in  claim 13 , wherein forming the terminal plate includes forming a top surface of the terminal plate to be flush with or lower than the top surface of the cap plate in the assembling of the terminal module to the cap plate. 
     
     
         15 . The method as claimed in  claim 11 , wherein manufacturing the cap plate includes:
 forming an upper recessed portion around a top surface of the terminal accommodating hole; and   forming a lower recessed portion around a bottom surface of the terminal accommodating hole.   
     
     
         16 . A terminal module, comprising:
 a top surface joint portion insertable into a terminal accommodating hole in a cap plate of a secondary battery, the top surface joint portion being attachable to a top surface of the cap plate and having an internal through-hole space;   a bottom surface joint portion insertable into the terminal accommodating hole and attachable to a bottom surface of the cap plate;   a terminal plate in the internal through-hole space of the top surface joint portion; and   an insulator between the terminal plate and each of the top surface joint portion and the bottom surface joint portion.   
     
     
         17 . The terminal module as claimed in  claim 16 , wherein the top surface joint portion includes a vertical wall surrounding the internal through-hole space, the vertical wall being bent radially outwardly from the through-hole space and attachable to the top surface of the cap plate. 
     
     
         18 . The terminal module as claimed in  claim 16 , wherein the insulator of the terminal module is between an inner circumferential surface of the top surface joint portion and an outer circumferential surface of the terminal plate. 
     
     
         19 . The terminal module as claimed in  claim 16 , wherein the insulator of the terminal module is integral with the bottom surface joint portion and the top surface joint portion. 
     
     
         20 . The terminal module as claimed in  claim 16 , wherein the terminal plate of the terminal module includes an interfacial metal layer.